Compensating wire-support



C. C. BLACKMORE. COMPENSATING WIRE SUPPORT.

APPLICATION FILED JUNE 7, 1918.

1,362,221, Patented Dec. 14, 1920.

INVEN TOR.

,degrees UNITED STATES PATENT OFFICE.

CHARLES C. BLACKMORE, OF DAYTON, OHIO.

GOMPENSATING WIRE-SUPPORT.

Application filed June 7',

To all whom it may concern:

Be itdrnown that 1, CHARLES C. BLACK- MORE, a citizen of the United States, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Compensating ire-Supports, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to compensating supports for wires and is designed more par-- ticularly for use in connection with telephone and telegraph lines.

Telephone and telegraph lines being strung in the open are, of course, subjected to the extremes of temperature for the localities through which they pass, and the variations in temperature cause relatively large of expansion and contraction in the wires. The weight of the metal in a long span of wire is considerable and when there is added to this weight the pull due to the contraction of the wire in very cold weather, the strain on the supporting pole, or structure, is very great. lVhere the line is straight and the spans on the opposite sides or" the pole are in substantial alinement, the strains on the two spans tend to equalize each other and the strains on the supporting pole is not so great, but where the successive spans are out of alinement, as where the line curves, the pole at the center of the curve is subjected to the combined strains of the spans on both sides thereof, which strains are exerted in a lateral direction. lVhen the pole carries but a few wires the strain thereon is not serious and the damage, if any, which results from the contraction of the wires will be to the wires themselves, but, where there is large number of wires, the strain is correspondingly multiplied and not infrequently the cross arm, or even the pole itself, breaks under the strain.

The object of the invention is to provide a device which may be interposed between the wire and the supporting pole to compensate for the contraction and expansion of the wire, thus permitting the wire to contract without imposing undue strain onitself or on the pole, and maintaining the wire taut when it is in an expanded condition.

It is also an object of the invention to provide such a device which can be easily attached to the supporting pole; which will occupy but little more space on the pole than does the usual insulator, and will not reduce Specification of Letters Patent.

?atented Dec. 14, 1920.

1918. Serial N0. 238,642.

the number of wires which can be strung on a cross arm; which can be produced at a low cost; and which will be of a simple, durable construction that will not be affected by exposure to the elements.

It is also an object 01" the invention to provide means for shifting a movable wireengaging device to compensate for the contraction and expansion of the wire.

In the accompanying drawings Figure l is a plan view of a cross arm of a telephone pole showing my invention applied thereto; Fig. 2 is a perspective view of one of the compensating devices; Fig. 3 is a section taken on the line 2 -2 of Fig. 1 showing one of the compensating devices in elevation; Fig. at is a sectional detail view of one of the insulators; and Fig. 5 is a plan view of a sli htly modified form of the invention.

In carrying out my invention I interpose between the line wire and the supporting structure a plurality of wire-engaging devices which are arranged out of alinement one with the other and with the wire so that when the wire is placed in engagement with all the wire-engaging devices a bend, or oilset will be formed therein. Any unusual tension on the wire, as would be caused by the contraction thereof in cold weather, will tend to straighten out the bend in the wire, and one or more of the wire-engaging devices is movably mounted so as to enable itto be moved toward a position in alinement with the other wire-engaging devices and thus permit the wire to straighten itself. Yieldable means are provided for resisting the movement of the wire-engaging device, or devices, toward such alined position, which means serves to restore the bend in the wire, when the latter expands, and to maintain the wire taut at all times. The manner of supporting and arranging the wire-engaging devices may vary widely, and the wire-engaging devices may be carried by any suitable part of a wire-supporting structure. The supporting structure is usually in the form of a cross arm carried by a pole, but it will, of course, be understood that the invention may be applied to any suitable support.

In the present drawing I have shown one embodiment of the invention, for the purpose of illustration. As here shown, the compensating device comprises three wireengaging devices which, preferably, are in the form of insulators 1, 2 and 8, and are 30 here shown the socket 9 as of a arranged out of alinement one with the other. In the arrangement illustrated the insulator 3 is fixed against movement on the supporting structure and, in the present instance, is mounted on the usual insulator pin 4; carried by the cross arm 5 of the pole 6, and is substantially in alinement with the span of the line wire on each side of the cross arm. The wire-engaging devices or insulators l and 2 are yieldably supported on opposite sides of the cross arm and out of alinement with the insulator 3, thus,'

when the line wire 7 is passed about the three insulators, as shown 1n F 1g. 2, it will be bent out of its course and an offset will be provided therein. In that construction of the device here illustrated the yieldable supports for the movable wire-engaging devices or insulators are in the form of resilient arms 8 which are mounted on the supporting structure, or cross arm, adjacent to the fixed wire-engaging device or insulator 3 and diverge therefrom. Preferably, the two arms are formed from a single piece of metal which is bent upon itself to form a socket 9 adapted to receive the insulator pin i and thus support the compensatii'ig device as a whole upon the cross arm or other part of the supporting structure. lVhile I have shape to embrace the insulator pin, it will be understood that it may be of any suitable character to connect the arms with the supporting structure. The two ends of the bar from which the devi e is formed curve outwardly,

as shown, and are provided at their ends with other sockets 10 to receive pins 11, which carry the insulators 1 and 2. The width of the bar from which the arms 8 are 40 formed may vary, but I prefer that it should be of a width not greater than the distance between the insulator and the cross arm so that when the socket has been placed about the insulator pin the insulator can be screwed on to the pin in the usual manner and will serve to retain the diverging arms thereon. It will be noted that the arrangement of the arms which carry the insulators 1 and 2 is such that the force exerted on one arm, which would tend to turn the same about its support on the insulator pin, will be equalized by the force exerted on the other arm and, consequently, the device will be retained in its proper position relative to the wire without fastening devices other than those mentioned.

As has been stated, the wire-engaging de vices may be of any suitable character, such as the ordinary insulators, to which the wires may be secured in the usual manner.

It may be desirable, however, to so connect the wires with the wire-engaging devices that they will have free movement relatively thereto and, to accomplish this, and also to facilitate the connecting of the wire with the compensating device, I have shown the several insulators as provided with circu1nferential grooves 12 adapted to receive the wire. lVhen the line wire is placed about the three insulators, as shown in Fig. 2, and lies within the grooves therein, it will be very effectively connected with the compensating device. fhe tension on the wire will be suficient to retain the same in the grooves and, so long as the wire lies in the grooves, it is held against vertical movement in either direction. This method of connecting the wires to the compensating device not only provides for the free movement of the wires relative to the insulators, but it enables the wire to be strung by simply looping the same about the insulators without applying thereto the usual tie-wires, thus greatly facilitating the stringing of the line.

The operation of the device will be readily understood from the foregoing description and it will be apparent that when the line wire is strung about the wire-engaging devices of the compensating device the resilient arms will hold the wire taut at all times, but that these arms will yield under unusual strains, such as a contraction of the wire or a high wind, to permit the bend in the wire to be straightened out, and thus increase to that extent the length of the wire, thereby compensating for the contraction thereof or for the displacement thereof by the wind. Gbviously this compensation relieves very largely the strain which would. otherwise be exerted upon the poles.

The construction de 'ibed will compensate for the expansion 1. 1d contraction of the wire but, obviously, the cmitraction of the wire, by causing the movement of the movable wire-engaging device against the tension of the resilient arm, will increase the tension which is applied to the wire. iVhile this, under ordinary circumstances, would not be serious, there may be circumstances under which it would be objectionable, and I have, therefore, provided means for automatically shifting a movable wire-engaging device to accommodate it to the changed po sition of the wire due to its contraction and expansion. This preferably accomplished by the use of a thermostatic device which will automatically shift the movable wireengaging device as the temperature varies. Thus, as the temperature falls, the movable wire-engaging device will be autoniaticall moved toward a position in alinement with the fixed wire-engaging device and the wire, and the wire will not be called upon to overcome the resistance of the yieldable supporting device. If it is desired to maintain a tension upon the wire by the use of a yicldable support for the wire-engaging device. this may be readily accomplished. The thermostatic device may talie any suitable form, but prefer that shown in Fig. 5, where I have shown a wire-supporting device, the main features of construction of which are similar to the device above described, but in which the two supporting arms are formed by two thermostatic couples, these couples being supported at those ends adjacent to the fixed wire-engaging device and having movable wire-en gaging devices at their outer or free ends. The thermostatic couple may be formed in any suitable manner, but I have here shown it as comprising flat bars of metal having different coefiicients of expansion and connected one with the other so that as the one bar contracts more rapidly than the other, it will tend to bend the two bars, constituting the arm, and thus shift the position of the movable wire-engaging device. By arranging the bar having the lower coei'licient of expansion on the inner side of the arm, that is, the side next to the line wire, the bending of the arm will shift the movable insulators toward ,a position in alinement with the fixed insulator and the line wire, the amount of this movement depend ing upon the temperature and, therefore, being in proportion to the amount of contraction of the line wire. Where it is desirable to use a yielding support, one of the bars constituting the thermostatic couple may be of resilient material and, in the present instance, I have used a bar of light spring steel, 1st, and a bar of zinc composition, 13, the two bars being rigidly connected one to the other.

While I have shown and described one embodiment of my invention, I wish it to be understood that I do not desire to be limited to the details thereof, as obvious modifications will occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A device of the character described comprising a fixed wire-engaging device, resilient arms diverging from said fixed wire-engaging device, and other wire-engaging devices carried by the respective arms at points remote from said fixed wireengaging device.

2. In a compensating device for line wires, the combination with a supporting structure, of a wire engaging member mounted thereon and arranged in substantial alinement with the line wire, other wire engaging members carried by said structure, arranged normally out of alinement with said line wire, and movable relatively to the first mentioned member, and separately yieldable devices tending to hold the respective last mentioned members out of alinement with the first mentioned member.

3. The combination with a supporting structure, of a wire-engaging member mounted thereon, yieldable devices mounted on said structure, and other wire-engaging members carried by the respective yieldable devices and arranged normally out of alinement with the first-mentioned wire-engaging member.

a. The combination with a supporting structure, of a wireengaging member mounted thereon, a pair of diverging yieldable arms carried by said structure at a point adjacent to said wire-engaging memher, and other wire-engaging members carried by said arms.

5. The combination with a supporting structure, of a pair of yieldable arms can ried by said structure, a wire-er 5 member arranged near the point of connection of said armswith said structure, and other wire-engaging members carried by said arms at points remote from the firstmentioned member.

6. The combination with a supporting structure, of a pair of diverging resilient arms carried by said structure, a wire-engaging member supported adjacent to the point from which said arms diverge, and other wire-engaging members carried by said arms at points remote from the firstmentioned member.

7. A device of the character described comprising a pair of resilient arms, wireengaging members supported near the ends of said arms, and another wire-engaging member supported adjacent to said arms between the first-mentioned members.

8. A device of the character described comprising a pair of diverging yieldable arms, wire-engaging devices carried by said arms near the outer ends thereof and another wire-engaging device supported adjacent to the point from which said arms diverge.

9. In a compensating device for a line wire, a pair of yieldable arms connected one to the other at their inner ends and having a socket to engage a supporting device at a point substantially in alinement with the line wire, and wire engaging members carried by said arms at points remote from said socket.

10. A compensating device for a line wire, comprising a bar of metal bent to form diverging yieldable arms and to form a socket at the apex of said arms to engage a supporting member and support said arms thereon, said arms having wire engaging devices near their outer ends.

11. In a compensating device for a line wire comprising a socket to engage a sup porting member in substantial alinement with said line wire, and having means to hold the same against turning movement relatively to said supporting member, a yieldable arm extending from said socket in a line intersecting the line of said wire and having wire engaging means near its outer end, the tension on said arm and the arrangement of said Wire engaging means being such that the latter will hold that part of said line wire which is engaged thereby normally out of alinement with the remainder of said wire.

12. A device of the character described comprising a bar of metal bent to form diverging resilient arms and to form a socket at the apex 01" said arms adapted to receive a supporting member, said arms being bent upon themselves a their outer ends to form sockets 13. A compensating device for a line wire, comprising a resilient arm mounted between the ends of said wire, extending normally at an acute angle to the length thereof and having one end fixed at a point substantially in alinement with said wire, a wire engaging device supported adjacent to the lined end of said arm, and a second wire engaging device carried by said arm and arranged out of alinement with said line wire.

let. In a device of the character described, a pair of yieldable arms adapted to be mounted on a supporting structure and having at their outer ends wire engaging parts arranged normally out of alinement one with the other and with said supporting structure.

15. In a device of the character described, a pair of yieldable arms arranged in intersecting lines and having wire engaging devices near their outer ends and also having a connecting portion adapted to engage a supporting member and support said arms thereon independently of the wire with which said device is in engagement.

16. A device of the character described,

comprising a rod having an intermediate portion in the form of a ring open on one side to permit it to embrace a supporting member, and having diverging yieldable arms extending from the opposite sides of said ring, said arms having wire engaging parts at their outer ends to engage said wire at points remote from said ring.

17. In a device of the character described, a plurality of wire-engaging devices arranged normally out of alinement with a line wire, one of said wire-engaging devices being fixed against movement relatively to the wire, and a thermostatic couple constituting a support for said movable wire-engaging device.

18. In a device of the character described, a fixed wire-engaging device, an arm mounted at a point adjacent to said fixed wire-engaging device, extending away from the line wire and comprising two bars of metal of different coeiiicients of expansion rigidly connected one with the other, and a second wire-engaging device supported by said arm.

19. 11 a device of the character described, a fixed wireengaging device, an arm mounted at a point adjacent to said fixed wire-engaging device, extending away from the line wire and comprising two bars of metal of different coefiicients of expansion rigidly connected one with the other, one of said bars being of resilient metal, and a second wire-engaging device supported by said arm.

In testimony whereof I my signature hereto.

CHARLES C. BLACKMORE 

